Preheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan.
In a mixing bowl, combine the mashed bananas and melted butter. Stir until well mixed.
Add the sugar, beaten egg, and vanilla extract to the banana mixture. Mix until combined.
Sprinkle the baking soda and salt over the mixture and stir to combine.
Gradually add the flour, mixing until just incorporated. Do not overmix.
Gently fold in the chopped strawberries.
Pour the batter into the prepared loaf pan and smooth the top.
Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Let the bread cool in the pan for about 10 minutes, then transfer to a wire rack to cool completely.